Hechosedrugs,
I can quickly think of three:
1) Trust in what you know, not in what you are told.
2) Males involved in home improvement projects are not good sources of information, especially short term memory issues - their brain is on the project, not on where they set things down.
3) It was nice that your mom humored him for a while, but she could have stopped sooner. But, on the other hand, that is part of the reason they are still married!
Keep coming back,
Jim